Improvement in apparatus for feeding pulverized fuel to furnaces



UNITED STATES PATENT OFFICE- JOHN Y. SMITH, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN APPARATUS EUR FEEDING PULVERIZED FUEL T0 FUHNACES.

Specication forming part of Letters Patent No. 120,680, dated November7, 1871 antedated November 4, 1871.

To all whom it may concern.'

Be it known that I, JOHN Y. SMITH, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a new and usefulImproved Apparatus for Feeding Finely-pulverized Fuel; and I do herebydeclare that the following is a full, clear, and exact description ofthe same, reference being had to the annexed drawing making part of thisspecification, in Which- Figure l is an elevation of the apparatus. Fig.2 is a longitudinal section. Fig. 3 is an end elevation. Fig. A is adetached view of the spiral feeder. Fig. 5 is a perspective view of thecask from which the pulverized fuel is fed, and Fig. 6 is a perspectiveview of a part of the apparatus.

In all the figures the same letters are employed in the designation ofparts which are identical.

This improvement relates to that class of apparatus in which provisionis made for feeding finely-comminuted fuel, to be burned While floatingin the atmosphere. The apparatus may be applied to any kind furnace orcombustionchamber. The special points of novelty will be specificallyindicated in the following description and specification of claims:

Either steam or a hot or cold blast or a current of gas may be employedas the means of carrying the iinely-pulverized fuel into thecombustionchamber. I prefer to use finely-powdered coal for the fuel,reduced by grinding in any suitable mill to a fme powder. The fuel, whenground, is passed into a box or cask having one close head and aflexible sack at the other end. When the cask has been lled a stringshould be tied around the sack and so fastened by a loop that, whenpassed through a small hole in the chine of the cask, the loop may bedisengaged by drawing this string, and thus the contents of the cask bedischarged into the hopper.

In the annexed drawing the cask is indicated by A. B is the hopper, intowhich the ne powder is discharged, and from which it is fed into thebarrel G of the injector. This is a tube of a uniform diameter of bore,closed at one end by a head, which may be conveniently removed so as topermit the spiral feed to be withdrawn when necessary. Within the barrelC is a spiral conveyer, D, revolving in the chamber of the barrel C.This may be actuated by gearing, as shown at N in Fig. 3, or by othermeans to be explained. In order to assist in dislodging the powder andto prevent its choking the feeder I cut grooves el around the spiralfeeder I) 5 these, cutting through the spiral flange, will tend todislodge the pulverulent material discharged from the hopper. The spiralfeeder passes through the head of barrel C, and is so constructed that alongitudinal motion may be imparted to it independently of its rotarymotion by means of the bifurcated lever. In case the coal should lodgein the barrel C the feeder D may be moved longitudinally in bothdirections by means ofthe lever D. The barrel D is surrounded by ajacket, E, both being so constructed as to leave an annular chamberbetween them, into which the air, steam, or gas is discharged througheither the pipe F or I2 The point of the barrel C should be beveled, asshown in Fig. 2. A ring, G, is placed in the chamber, and is to besimilarly beveled. This ring is operated by a stud projecting throughslots in the jacket E, so that by moving it toward or from the end ofthe barrel G the force and quantity of the blast may be regulated at thewill of the operator. While the entering blast is thus susceptible ofregulation, the quantity of pulverulent matter may also be controlled bymeans of the valve H, which, being actuated by the rod H', may be soarranged in relation to the mouth of the barrel G as to regulate thesupply of the pulverulent material carried forward by means of thespiral feeder. The rod H, passed through a hole bored through the spiralfeeder, is regulated by means of the head H2, screwed into the end ofthe feeder. l have already indicated the mode of revolving the feeder bymeans of the spurwheels N N but I have shown in Figs. 2 and 6 anothermode, which in most cases I would prefer to use, as it may be employedwhere it is not 'convenient to apply independent power tothe actuationof the feeder. I is a case inclosing a fan or other wheel, to berevolved by the force of the current of .air, steam, or gas entering atI1 and escaping at I2, to be discharged into the injector or into thefurnace. rlhe wheel will be caused to rotate rapidly by the force ofthis current, and its shaft, passing through a suitable stuffing-box inthe head of the-fan-case, carries, or, by means of intermediate gearing,communicates, motion to the worm K, which engages corthey are exposed.

respondingly-spiral cogs on the face of a pinion, K', on the shaft ofthe feeder D, which will be rotated by the motion of the wind-wheel.rIhe lever Dl is attached to a plate, M, having two slots, one in thearc of a circle and the other radial, in. which the bifurcated lever issecured by means of set-nuts. The one on the segmental slot beingloosened, the feeder D may be operated longitudinallyfor the purposealready eX- plained. By loosening the set-nut at the radial slot thepoints of the lever may be disengaged from the groove d', and the spiralfeeder drawn out of the barrel C to .admit a rod to be passed throughthe injector. The inclined face of the ring G will cause the blast, whenpassing the mouth of the barrel C, to have the form of a cone, into thecenter of which the pulverulent material will be discharged, therebyinsuring the thorough intermingling of the fuel with the air, steam, orgas before entering the combustion-chamber. The blast is dischargedthrough the mouth-piece O, which is attached to the inside of the mouthof the jacket E by a balljoint, so as to permit the mouth-piece to bedirected toward different parts of the furnace or combustion-chamber, asmay be preferred.

Great difficulty has been experienced in the application offuel-injectors to practical use by reason of the inability of metallicmouth-pieces to withstand the very high temperature to which To meetthis dificulty I propose to construct or line the mouth-piece with arefractory substance formed of pulverized quartz, prepared in the mannerset forth fully in a specication filed in an application made at thesame time as this. In many metallurgie operations it is desirable tominglefvarious gaseous or liquid iniiamlnable substan ceY with the coalfor the purpose of modifying the iiame according to the requirement ofthe art or operation. I have indicated at P a receiver, connected by apipe, P, with the chamber where the pulverized fuel is mingled with theblast, by means of which the desired modification may be produced, othergases or iniiammable liquids being introduced at that point.

I aln aware that spiral conveyors have heretofore been used for thepurpose of feeding pulverulent fuel; and in a former application of myown I have set forth an apparatus for feeding pulverized fuel in a blastof air, steam, or gas;

and I do not, therefore, claim either of these features broadly. f

What I claim as my invention, and desire to secure by Letters Patent,is-` l. In combination with the injector-hopper B, the cash A providedwith the flexible sackmouth, and arranged to operate substantially asset forth.

2. The barrel C when constructed With a uniform bore and used incombination with the removable spiral feeder D, substantially as setforth.

8. The spiral feeder D when constructed with the transverse grooves d,substantially as set forth.

4. In combination with the spiral feeder D, the lever D for giving alongitudinal motion to the former while rotating on its axis,substantially as set forth.

5. In combination with the lever D', the plate M, constructed with thesegmental and radial slots, substantially as and for the purpose setforth.

6. rlhe spiral feeder D, in combination with the endless screw K,communicating to the feeder a rotary motion derived from the action ofthe blast on the fan-wheel in the case I, substantially as set forth.

7 In combination with the barrel C and jacket E, the adjustable ring Gfor regulating the blast, substantially in the manner set forth.

8. In combination with the barrel Gand spiral feeder D, the adjustablevalve H, arranged to operate substantially as set forth.

9. In combination with a feed-injector, an adjustable mouth-piece, O,arranged to operate substantially as set forth.

l0. A mouth-piece, O, made of silex, substantially as described.

Il. In combination with the feeding device D C and the jacket E, thepipes Pf, arranged to di scharge gases or combustible liquids into thepulverized fuel when mingled with the air or other blast, substantiallyin the manner set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN Y. SMITH.

